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991.
Radioimmunoguided surgery benefits for recurrent colorectal cancer   总被引:2,自引:0,他引:2  
Background: Despite new adjuvant therapy, 50% of patients with colon cancer will have recurrent disease. This study investigated the use of a radiolabeled monoclonal antibody in locating occult tumor during surgery for recurrent colorectal cancer. Methods: Twenty-two patients with recurrent colorectal cancer underwent surgery using the radioimmunoguided surgery (RIGS) system. All patients were subjected to abdominal and chest computed tomography (CT). Before surgery, patients were injected with the CC49 monoclonal antibody (MoAb), anti-TAG antibody labeled with125I. Ten patients with elevated carcinoembryonic antigen (CEA) levels and no CT findings had a scintigraphy scan with an anti-CEA MoAb labeled with99Tc. Human antimouse antibody levels of these patients were within normal limits. Surgical exploration including liver ultrasound examination was followed by survey with a gamma-detecting probe (GDP). Results: There was MoAb tumor localization in 100% of the patients. CT found nine tumor sites, traditional surgical exploration 30, and the GDP 51, with 44 confirmed by pathology (hematoxylin and eosin). The RIGS system found occult tumor in 10 patients (45.4%) and resulted in major changes in surgical procedure in 11 patients. In the 10 patients who had scintigraphy scans, 10 tumor sites were identified, whereas RIGS found an additional eight sites. Conclusion: RIGS technology offers a substantial benefit for patients undergoing surgery for recurrent colorectal cancer and a better chance of finding recurrent tumor intraoperatively in patients who have elevated CEA levels with no other CT findings. Presented at the Annual Cancer Symposium of The Society of Surgical Oncology, Atlanta, Georgia, March 21–24, 1996.  相似文献   
992.
Stress echocardiography has been considered an accurate method for the diagnosis of coronary artery disease in hypertensive patients and in patients with left ventricular hypertrophy. In contrast, the specificity of myocardial perfusion scintigraphy in these patients has been questioned. The aim of this study was to compare the accuracy of these two imaging modalities in conjunction with dobutamine stress test for the diagnosis of coronary artery disease in hypertensive patients with and without left ventricular hypertrophy. Dobutamine (up to 40 μg kg–1min–1) stress echocardiography in conjunction with sestamibi (MIBI) single-photon emission tomography (SPET) was performed in 84 patients with the diagnosis of systemic hypertension who had been referred for evaluation of myocardial ischaemia. Ischaemia was defined as new or worsened wall motion abnormalities at echocardiography and reversible perfusion defects at SPET. Significant coronary artery disease (≥50% luminal diameter stenosis) was detected in 66 patients (79%). The sensitivity, specificity and accuracy of the ischaemic pattern at echocardiography for the diagnosis of coronary artery disease were 73% (CI 63%–82%), 83% (CI 75%–91%) and 75% (CI 66%–84%), those for MIBI were 67% (CI 57%–77%), 83% (CI 75%–91%) and 70% (CI 60%–80%) respectively (P = NS vs echocardiography). Significant stenosis was detected in 123 (49%) of the 252 analysed coronary arteries. The sensitivity, specificity and accuracy of echocardiography for the regional diagnosis of coronary artery disease were 63% (CI 56%–69%), 90% (CI 86%–94%) and 77% (CI 72%–82%). Those for MIBI were 58% (CI 51%–64%), 91% (CI 87%–94%) and 75% (CI 69%–80) respectively (P = NS vs echocardiography). Left ventricular hypertrophy was detected in 59 patients (70%) by echocardiography and did not influence the overall or regional specificity of echocardiography or MIBI SPET. It is concluded that in hypertensive patients, dobutamine stress echocardiography and MIBI SPET have a comparable accuracy for the overall and regional diagnosis of coronary artery disease. Hypertensive patients with or without left ventricular hypertrophy should not be considered unsuitable candidates for stress myocardial perfusion scintigraphy. Received 10 July and in revised form 19 September 1997  相似文献   
993.
近红外线乳腺扫描对诊断乳腺癌,特别对早期乳癌具有高度的敏感性和诊断特异性,根据1500例证实的分析,近红外线乳腺扫描诊断率T1—T2期为95%;T1期直径<1cm及TO期乳癌诊断率为85%。 作者首先提出近红外线乳腺扫描的所见15种分型,本文叙述了近红外线乳腺检查的诊断原则及其诊断价值。 由于近红外线乳腺扫描具有高敏感性而且是无损害的简易的检查方法,我们认为应作为乳腺的常规检查及普查时的首选检查方法。  相似文献   
994.
995.
Complex interactions in Parkinson's disease: a two-phased approach.   总被引:4,自引:0,他引:4  
The identification of pathogenic mutations in the three genes alpha-synuclein, parkin, and ubiquitin carboxy-terminal hydrolase L1 (UCHL1) has elucidated the ubiquitin proteasome system (UPS) and its potential role as a causal pathway in Parkinson's disease (PD). In addition, polymorphisms of these three genes have been shown to be independently associated with PD. In a sample of 298 unrelated PD cases and 185 controls, we applied a two-phased approach of recursive partitioning and logistic regression analyses to explore complex interactions. For women only, we observed an epistatic interaction of UCHL1 and alpha-synuclein genotypes with significant effects on PD risk (odds ratio = 2.42; P = 0.003). Our findings are consistent with the hypothesis that PD is a multigenic disorder of the UPS.  相似文献   
996.
A 15-year-old boy with a terminal deletion of the short arm of chromosome 4 is described. The patient has a mild clinical phenotype that is incompatible with Wolf-Hirschhorn syndrome. Careful neurological examination including CT scan did not show any signs of Huntington disease. The chromosomal breakpoint was analyzed by means of polymorphic DNA probes localized close to the tentative Huntington (HD) locus. The breakage has occurred between D4S43 and D4S90 loci and thus deletes part of the chromosomal candidate regions for the HD locus. © 1992 Wiley-Liss, Inc.  相似文献   
997.
彩色多普勒超声和二维超声心动图并用,不仅可观察和了解心脏解剖、形态及腔室大小,又能观察血流动力学改变。我们从1991年11月至1992年11月间应用上述方法诊断先天性心脏病共18例,均经我院和外院手术证实:室间隔缺损7例;房间隔缺损6例;动脉导管未闭5例,其中1例误诊为肺动脉瓣狭窄,诊断准确率达94.4%。我们认为彩色多普勒诊断先天性心脏病方法安全,准确无损伤,为临床及术前提供了较可靠的诊断依据,但检查者必须了解心脏及大血管的解剖关系,结合临床才能提高诊断准确率,减少漏、误诊的发生。  相似文献   
998.
Possible protective immunity in human opisthorchiasis   总被引:4,自引:0,他引:4  
Chronic infections with the liver flukes Opisthorchis viverrini and Clonorchis sinensis affect over 30 million people in southeastern Asia. With ongoing exposure, reinfection readily occurs following curative treatment and cumulative infections result in significant morbidity and a predisposition to cholangiocarcinoma. Though protective immunity has never been described in human opisthorchiasis, heterogeneity in worm burden occurs and a small number of exposed residents of endemic areas remain apparently uninfected. To explore the nature of this heterogeneity, we compared levels of serum antibody (Ab) to O. viverrini measured by an enzyme-linked immunosor-bent assay in 83 stool egg-positive and 49 stool egg-negative residents of an O. viverrini-endemic area in Thailand. Compared to the egg-positive residents, the egg-negative group had significantly higher levels of immunoglobulin (Ig)G, IgA and IgM to adult worm homogenate (AWH) and total Ab to metacercaria homogenate (MH). Furthermore, immunoblot analyses revealed that a significantly higher proportion of sera from the egg-negative residents had IgA reactivity against a 38-k Da AWH antigen and IgM reactivity against carbohydrate epitopes of a 42-k Da AWH glycoprotein antigen. These findings support a hypothesis that the egg-negative group includes individuals who may be immunologically resistant to this usually chronic infection.  相似文献   
999.
Disturbances of visual cognition, visuomotor performance, and visual memory have been described frequently in Huntington's disease (HD). Early stage visual abnormalities could contribute to these deficits. We evaluated visual processing in 20 control subjects who were non-gene carriers at risk for HD, nine presymptomatic gene-positive subjects, and eight subjects with a recent diagnosis of Huntington's disease. Visual perceptual tests of contrast sensitivity and motion discrimination were used to probe early stage visual processing. Extraocular movements were evaluated in a neurologic examination, and the Digit Symbol test was used to test visual motor performance. Contrast sensitivity did not differ among the three groups. Motion discrimination was impaired in HD subjects but not in the presymptomatic gene carriers when compared to gene noncarriers. Among gene carriers, impaired motion discrimination performance was associated with poorer Digit Symbol performance and extraocular abnormalities. These findings suggest that the early stages of HD are associated with disturbances of motion perception as well as disruptions of visual motor and ocular motor performance.  相似文献   
1000.
Percutaneous transvenous mitral commissurotomy was performed successfully via the transjugular approach in a patient with severe rheumatic mitral stenosis and obstruction of the inferior vena cava due to prior liver transplantation. This case demonstrates the advantage of the jugular approach in patients with difficult anatomy.  相似文献   
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